1. Field of the Invention
The present invention relates to a roaster for automatically roasting a wide variety of food including chicken, beef, pork, fish, shrimps, and vegetables secured on a spit or skewer.
2. Description of the Prior Art
Automatic roasters for skewered meat are known, wherein a number of spits or skewers secured with various kinds of raw meat are spacedly mounted on an endless chain moving through a space defined by facing heat sources to roast the skewered meat. Generally, there are two types of the conventional roasters. One type arranges the heat source horizontally while the other arranges the heat source vertically. An automatic skewered food roaster having vertical heat sources is disclosed, for example, in a Japanese Patent Publication (after examination) No. 54(1979)-6630, as well as a Japanese Utility Model Publication (after examination) No. 56(1981)-33476. The disclosed roasters, when compared with the horizontal style, have the advantages that (1) the meat juice is not dropped onto the heat source (2) and almost no smoke is produced while roasting, and (3) heat can be preliminarily applied to the skewered meat by utilizing ascending heat generated from the heat sources, before the skewered meat is carried into a space formed between the heat sources for roasting. At present, this vertical styled automatic skewered food roaster is widely used. In order to effectively preliminarily heat skewered meat by reserving the ascending heat in a vertical automatic skewered food roaster, Patent Publication No. 54(1979)-6630, teaches that a heat barrel containing right and left heat sources therein be formed at its upper portion with a hollow portion for permitting the skewered food to pass therethrough. On the other hand, in the skewered food roaster discussed in the Utility Model Publication No. 56(1981)-33476, a reflection plate formed in a shape of an inclining roof is disposed above the right and left heat source in order to increase the heat reserving effect.
However, the heat reserving means by forming the hollow portion has the disadvantage that the ascending heat is often dispersed within the hollow portion. That is, the ascending heat is suddenly dispersed from a discharge port formed at the top of the hollow portion. As a result, an insufficient heat reserving effect is obtained. Similarly, in the case of the above mentioned reflection plate formed in an inclining roof shape, since the ascending heat is suddenly raised due to the chimney effect of the inclining roof shaped reflection plate, only limited spaces at the upper ends of the reflection plates will form a temperature distribution suitable for the preheating, and a sufficiently high temperature suitable for the preheating can not be obtained in the area at the inside of the reflection plates. Because of the foregoing reasons, none of the conventional skewered food roasters described can sufficiently preheat the skewered food. Furthermore, since the conventional skewered food roasters employ a gas burner of a heat radiation type, considerable piping is required before use. It is not only a nuisance job to do the piping, but also there exists such a problem that the conventional skewered food roasters of the type just described are not always permitted to be used in all places since it would be unsafe.
The present invention was developed in order to overcome the problems inherent in the prior art devices.